A four-week-old kitten named P-54 is believed to be the product of mountain lion inbreeding, according to a statement released by the National Park Service on Monday.
The cub's mother is P-23. Its father is believed to be P-23's half-brother P-30.
While reproduction within the mountain lion population south of the 101 is generally a good sign for the species, inbreeding could also lead to serious problems for the population in the future, Seth Riley, a wildlife ecologist with the NPS, told KPCC.
"The mountain lions south of the 101 are completely cut off to the north by development and the 101 freeway," he said. "As of a few years ago, before one male mountain lion crossed [the 101] into the Santa Monica Mountains, the genetic diversity was lower than anything ever before seen in the West."
Last November, wildlife activists acquired a strategically located 71-acre swath of land between the Santa Monica Mountains and Simi Valley that they hope will be home to the area's first overpass for wildlife.
If constructed, the overpass could help reduce the amount of inbreeding south of the 101 freeway by connecting mountain lion populations and increasing genetic diversity, according to the Mountains Recreation and Conservation Authority.
Right now, P-54 seems healthy, and the population in the Santa Monica Mountains lives fairly well, according to Riley. The survival rate for kittens is good. Adults seem to find plenty of deer to eat and stay out of people's way, he said.
But if this population isn't connected with the larger one to the north, in Simi Valley, serious physical effects and deformities could begin to appear in the animals, he said.
When lion populations in Florida began inbreeding, that state started to see lower reproduction rates, kinked tails and holes in their hearts, Riley said. Many males had one or both testes that were undescended. They were sterile, and the lions, also called panthers or cougars, almost went extinct.
"We don't know what it would look like [in L.A.]," Riley said. "But it's not good, obviously."
The DNA results confirming P-30 as P-54's father should be available in several weeks, Riley said.
The National Park Service has been studying mountain lions since 2002 to determine how they survive in an increasingly fragmented and urbanized environment, according to the NPS statement.